Looking for a pair of Subs, 1ohm

Guys WHat would be the difference between a 15" subs with 500W rms and a 12" sub with the same RMs 500W

3"?    Sorry, couldn't resist..  Don't get hung up on power ratings as they mean very little to how a speaker will sound.  In general, a 15" loudspeaker driver will have more authority and generate more SPL at the lowest frequencies than a 12" from the same manufacturer.  It will also tend to be "flabbier" and not sound as tight, especially in the higher ranges.  But that is also a function of the enclosure design and the intended application and lots of other design and installation factors, so it is not a generally true statement.  Also, if you're talking about a 15" loudspeaker from Brand A and a 12" from Brand B, you cannot acurately compare them based on cone size or printed specs.  You have to compare them side by side with the same amplifier and similar enclosures to really see any  differences.  And there are plenty of 12" drivers out there that will outperform some 15" drivers... Support the12volt.com

OH, I have a SOund advice like 5 minutes from my house, I will take a look at it. t hank you for your help....

I went to Sound Advie, they didnt have the DVC dual 4 ohms only single voice. but they were 430.00 EACH ONE the 12, and they can order for me and it takes like 2 -3 weeks. I told them not way... That too much $#$$$$$. Which other subs Not THAT Expensive could i get.

YYEs, I know they were expensive, the think is i just got new setup for my new car which i spend like US 3.500 ANd I used to have the PIoneer Premier SPL series, which they sound nice, BUt i sold them and Now I want to spend like $500.. I was looking looking at the Kicker L7 the 12", Because my amp is 1100 W rms at 1 ohm., so i need to get like a 500W rms each subs DVC 4 ohm

Oh I want MORE SPL than SQ

SPL eh?  Two 12" DVC 4-ohm drivers that can handle the power from your amp at 1100 watts, eh?  $500 eh?  Buy a pair of these Kove drivers from Parts Express and have a ported enclosure built for them.  Pound, baby, pound!Support the12volt.com

Is that brand good? have you ever hear them.